Film processing apparatus



Jan. 27, 1970 F. R. GRUBER FILM PROCESSING APPARATUS Filed Dec. 21. 1966m u m R b m m m ATTORNEY United States Patent 3,491,674 FILM PROCESSINGAPPARATUS Francois Rene Gruber, Wilmington, Mass., assignor to ItekCorporation, Lexington, Mass., a corporation of Delaware Filed Dec. 21,1966, Ser. No. 605,133 Int. Cl. G03d 3/00, 3/12 US. Cl. 95--89 19 ClaimsABSTRACT OF THE DISCLOSURE Photographic film processing apparatuscomprising a fluid applicator and a barrier support. The fluidapplicator applies a uniform layer of fluid to the film at speeds in theneighborhood of 100 feet per minute. The barrier is provided with smoothwalls parallel to the film path and extending into the applicator.

BACKGROUND OF INVENTION Field of the invention This invention falls inthe class of machines and certain generally related articles andprocesses for the fluid treatment of strip material. A preferredembodiment of this invention falls in the class of machines, articlesand processes for the production of pictures by the fluid treatment ofphotographic film containing a latent image, which latent image wasobtained by the action of activating radiation, electron beams, and thelike upon a medium sensitive to the same.

Description of the prior art and objects Present systems for the rapidprocessing of photographic film are subject to a number of difficulties.These difficulties are especially great in high speed automatic filmprocessing equipment used to process film for data storage on film,microfilming and aerial photography. In such applications there may beas many as one hundred lines per millimeter of film. Any unevendevelopment of the film can result in serious error when the film isrecovered and printed out. In the processing of aerial photographs, forexample, development must be as even as possible since subleties oflight and shade play a very important part in subsequent interpretationof these photographs. Displacement of the emulsion gel may also causeserious difliculties since uneven refraction of light passing throughthe gel can cause distortion of the recorded image. Serious errors whenthe information on the film is printed out can thus occur. For anyapplication requiring a high degree of accuracy such errors must beavoided. A further problem of prior art film processing equipment is theabrasion caused to the film in the passage of the film over a plate,roller, or other surface. Even a minor scratch or blur may be criticalwhere high accuracy of the recorded information is required. Forexample, to obtain the high speed desired in processing equipment it isoften necessary to apply a large plurality of upper and lower rollersthrough which the vertically oriented film passes. To obtain thesespeeds it may be necessary to employ up to 240 rollers. The accumulationof sediment on the roller surface and/or uneven alignment of the rollersmay cause abrasion and/or uneven development of the film surfaces. Onthe other hand, processing equipment such as described in US. Patent No.3,192,846, while eliminating a number of rollers needed for filmprocessing also may cause uneven film development and/ or displacementof the gel surface due to uneven fluid flow and/or uneven turbulence ofthe fluid. In attempting to overcome these difficulties when operatingat high speeds, e.g., at speeds up to 100 feet per minute, large3,491,674 Patented Jan. 27, 1970 SUMMARY OF THE INVENTION In accordancewith one embodiment of the invention a pair of liquid applicatorsdispense very thin sheets of processing fluid into a narrow channelwhich contains the moving film to be processed. The liquid is initiallyapplied as thin sheets to the upper and lower film surfaces at a smallangle of attack with respect to the surfaces to prevent uneven overallturbulence which may cause destructive film flutter or resonance. Theuse of a narrow channel enables the employment of surprisingly smallquantities of fluid which reduces the sizes of the recirculation pumps,while the use of liquid applicators having uniform cross sections alongthe width of the film together with the narrow channel provide forpressure and development uniformity. The fluid dispensing nozzle and thechannel forming barrier means may be in part formed of a unitarystructure to eliminate undesirable rough edges which could result infilm abrasion and turbulence producing components.

The principal object of the present invention is to provide a new andimproved film processor. A further object of this invention is toprovide a high speed film processing apparatus which provides foreflective agitation of the processing fluid at the film surface.

Another object of this invention is to provide a film processingapparatus of the above character which applies processing fluid to afilm with a minimum of displacement of the film in emulsion.

Another object of this invention is to provide a high speed filmprocessing apparatus of the above character in which the dangers ofdamage to film during processing are at a minimum.

Another object of this invention is to provide a film processingapparatus which operates at very high speed and yet requires asurprisingly small quantity of processing fluid.

Another object of this invention is to provide a film processing methodand apparatus of the above character in which the film is supported by auniform fluid bearing layer of processing fluid as the film goes throughthe processing stage.

A further object of this invention is to provide a film processingmethod and apparatus of the above character in which the film issupported by a uniform fluid bearing layer of processing fluid as thefilm goes through the processing stage.

A further object of this invention is to provide systems, methods, andapparatus for the high speed processing of film in which relativemovement between the film and a thin layer of processing fluid createsuniform turbulence in the field adjacent to the film, and preventsoverall uneven turbulence which causes destructive film flutter.

A further object of this invention is to provide systems, methods, andapparatus for the fluid treatment of film in which the film is developedat a high degree of uniformity and accuracy.

A further object of this invention is to provide systems, methods, andapparatus for processing photographic film in which processing time hasbeen substantially reduced.

Another object is to obtain greater control of maximum density andcontrast for a given temperature of developer solution.

Another object of this invention is to provide a method for continuouslyprocessing strip photographic film.

Another object of this invention is to provide systems, methods, andapparatus of the above character which are inexpensive and reliable inoperation.

These and other objects will be apparent from the disclosure whichfollows:

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 3 is a view of a smooth surfacewhich forms part of the barrier means and fluid applicator means ofFIGURES 1 and 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In accordance with thisinvention a continuous moving film is processed by a data processingapparatus comprising a fluid applicator and a barrier means. The fluidapplicator delivers a thin fluid layer of fluid having uniform pressureacross the surface of the continuous moving film. The angle of incidenceof the film layer with respect to the film is maintained at less thanabout 45 degrees and is preferable from about degrees to about 25degrees such that the film layer possessing substantially uniformturbulence within given laminae to provide overall laminar flow betweenthe barrier means and the film wherein substantially none of theemulsion gel of the film is displaced. The fluid layer is applied to thefilm as a uniform layer across the film. The fluid layer has a width ofup to about $5 inch and preferably about 1 inch. However, the width ofthis fluid layer may be varied somewhat depending upon the viscosity andcomposition of the fluid layer velocity of the fluid layer and thecoeflicient of friction of the barrier means and the film with respectto the fluid layer. The fluid applicator is preferably joined to thebarrier means. For example, in certain applications it may be desirableto utilize a barrier means composed of a fluid having a viscositysubstantially different than the viscosity of the processing fluid. Onthe other hand, certain embodiments of this invention may comprisebarrier means such as in the form of a moving belt. The barrier means isa noncompressible composition and/o1 structure spaced at a distance fromthe film, such distance being substantially the same as the width of thefluid layer which is applied by the fluid applicator to the film. Thebarrier means helps to maintain a fluid layer across the film having auniform flow rate and uniform width and pressure. The coeflicient offriction of the barrier means with respect to the fluid layer can bevaried depending upon the viscosity of the fluid layer, speed of thefluid layer, nature of the film being processed, and like factors knownto one skilled in the art. For example, a material having a lowcoeflicient of friction such as polytetrafluoroethylene may be used whenextremely high speed film processing, such as 100 feet per minute isdesired. In such a process the fluid layer may preferably be less thanabout 4 of an inch in width.

A preferred embodiment of this invention involves using pairs of thefilm processing units of this invention on both sides of the film, eachunit being spaced at substantially equal distances from the film and insuch a position that the pressure on one side is substantially balancedby the pressure on the other side of the film. In this manner both sidesof the film can be processed in one step. On the other hand, where it isdesired to process only one side of the film it may be desirable toutilize the apparatus of this invention on only one side of the film andto utilize roller bearings, air hearings or other support means known tothe art on the other side of the film. A series of paired dataprocessing units may be combined to form a complete data processingsystem utilizing one or a series of different fluids for processing offilm.

It is understood that the data processing system of this invention maybe utilized in series to form a film path through which film can beprocessed.

FIGURES 1 and 2 show a preferred embodiment of this invention whereinthe fluid applicators 11, 21 and barrier means 12, 22 form unitary filmprocessing ap' paratus (or units) 10, 20 and comprise fluid inlet gaps13, 23. The film, 3, passes between the pair of film data processingunits 10, and 20 in a plane substantially parallel to the planes formedby the planes of the barrier means on each side of the film. The smoothsurface, 30,, of FIGURE 3 is an amplified view of 17 and 27, and acts asa barrier means for maintaining the uniform fluid flow between the filmand said smooth surface, a means of distributing a uniform fluidpressure to the fluid distributing chambers, 14, 24 and from the fluidinlet chambers, 15, 25 and provides a smooth joinder of the fluidapplicator and the barrier means thereby eliminating rough edges whichcause undue turbulence and abrasion of film surfaces. The apertures 31,may be adjusted in size and position to obtain the desired uniformpressure in the fluid distributing chambers. The smooth surfaces 17, 27are preferably bonded to the other part of the barrier means, 12, 22 bymeans of adhesive, screws, such as 18, bolts, or the like. The screws 19are used to join the back of the applicators to the applicators therebyforming the fluid distributing chambers 14, 24. Thus the fluidapplicator of the preferred embodiment of FIGURES l and 2 may be readilydisassembled for cleaning, repairs, maintenance, etc.

The applicators may be arranged so that the direction of the flow offluid is in any direction in relation to the direction which the film ispassing so long as the fluid forms a film of uniform turbulence andthickness between the barrier means and the film. It is however,preferred that the fluid flows in the direction in which the film istraveling since the fluid serves the additional function of propellingthe film through the developer system thereby eliminating the need ofrollers or other type of propelling means. Such a system also has theadvantage of being self-threading, i.e., the film does not have to behand threaded through the data processing system of this invention. Thehigh speed data processing system of this invention may, of course, beprovided with station-s for reversing the direction of the film flow toform a number of tiers of tandemly mounted data processing units,thereby enabling the data processing system to be stored in a verycompact amount of space. The fluid applicator may be of varying widthand shapes depending upon the width, shape, and direction of flow offilm being processed. For example, a cylindrical shape film would use acylindrical shaped fluid applicator and barrier means. The barrier meansof the data processing apparatus of this invention can also be curved inorder to change the direction of the flow of the film.

A preferred embodiment of the fluid applicator means of this inventionwherein a fluid layer possessing substantially uniform turbulence andsubstantially uniform laminar flow is applied to a continuous movingfilm comprises (a) an inlet fluid holding chamber 15, 25 of FIG- URE 2,wherein the fluid pressure is built up and provided with means forcontrollably allowing the fluid to pass to a (b) fluid distributingchamber 14, 24 of FIG- URE 2, which is provided with a uniform outletaperture for allowing a fluid layer to pass into the space between thebarrier means and the film path.

This invention provides a high speed data processing apparatus whichmaintains a uniform fluid bearing layer of processing fluid forsupporting a continuous moving film which is going through the processstage. This film processing apparatus provides for effective agitationof the processing fluid at the film surface with a uniform turbulence,therefore, it is now possible to process film at very high speeds, up toabout 100 feet per minute, and obtain as a final product developed filmand prints of 'very high quality.

It will be understood that this invention can also be applied forprocessing strip material other than photographic film in the strictsense. For example, data storage tapes wherein the information has beenrecorded magnetically, by pressure tracing or by a like process may betreated with the apparatus of this invention.

Therefore, it can be seen that this invention is applicable to any typetape or material where it is desired to :apply a fluid layer havinguniform turbulence and uniform laminar flow across said tape.

While there have been described above what are presently believed to bethe preferred forms of the invention, variations thereof will be obviousto those skilled in the art. All such changes and variations which fallwithin the spirit of the invention are intended to be covered by thegeneric terms in the appended claims, which are variably worded to thatend.

What is claimed is:

1. In a high speed processing apparatus comprising (1) a fluidapplicator means for applying a substantially uniform processing fluidlayer to a continuous moving film and (2) a barrier means which acts asa support for maintaining said fluid layer against the film, theimprovement comprising providing said fluid applicat r means with ameans for applying a thin fluid layer having a width up to inch ofsubstantially uniform width and pressure to the film at an angle ofincidence of the thin fluid layer across the film of less than about 45degrees and wherein the barrier means comprises smooth wallssubstantially parallel to the film path and extending for a substantialdistance along the film path and into the applicator means and whereinthe processing apparatus comprises means for moving said fluid at highspeeds in the neighborhood of 100 feet per minute and wherein thebarrier means is adjacent to the film in order to maintain a thin fluidlayer bet-ween the film and barrier means in order to maintain a fluidlayer possessing substantially uniform turbulence and substantiallyuniform overall laminar flow between said barrier means and said film.

2. In a high speed data processing apparatus comprising (1) a liquidapplicator for applying a processing uniform liquid layer against thefilm, the improvement comprising providing said liquid applicator with ameans for applying a thin liquid layer of substantially uniform widthand pressure across the film at an angle of incidence of the thin liquidlayer to the film of less than about 45 degrees and wherein theprocessing apparatus comprises means for moving said fluid at highspeeds in the neighborhood of 100 feet per minute and a barrier meansadjacent to the film for maintaining a thin liquid layer having a widthup to inch against the film in order to maintain a liquid layerpossessing substantially uniform turbulence and substantially overalluniform laminar flow between said barrier means and said film andwherein the barrier means comprises smooth walls substantially arallelto the film path and extending for a substantial distance along the filmpath and into the applicator means.

3. A high speed data processing apparatus as in claim 2 wherein saidliquid applicator comprises (a) an inlet liquid holding chamber whereinthe liquid pressure is built up and provided with means for controllablyallowing the fluid to pass to a (b) liquid distributing chamber which isprovided with a uniform thin outlet aperture, for allowing the liquidlayer to pass into the space between the barrier means and the film.

4. A high speed data processing apparatus as in claim 3 wherein saidthin outlet aperture has a width of less than inch.

5. A high speed data processing apparatus as in claim 2 wherein saidliquid applicator has a thin outlet aperture for applying the liquidlayer to the film.

6. A high speed data processing apparatus as in claim 2 wherein theliquid applicator is oriented to apply a liquid layer to a continuousmoving film in the direction in which the film is traveling.

7. A high speed data processing apparatus as in claim 2 wherein saidapplicator and said barrier means form a uriitary structure.

8. A high speed data processing apparatus as in claim 7 furtherincluding means for enabling disassembling of said apparatus for ease ofmaintenance.

9. A high speed data processing apparatus as in claim 8 wherein saidbarrier means further comprises a smooth sheet which extends itself intothe applicator and forms a wall between an inlet fluid holding chamberand an outlet fluid dispensing chamber of said applicator, therebyproviding a smooth wall along which the fluid can travel from theapplicator to the barrier means.

10. A high speed data processing apparatus as in claim 9 wherein saidsmooth sheet is composed of stainless steel.

11. A high speed data processing apparatus as in claim 9 wherein saidsmooth sheet is composed of polytetrafluoroethylene.

12. The combination as set forth in claim 2 wherein said angle ofincidence is from about 15 degrees to about 25 degrees.

13. The combination as set forth in claim 3 wherein said angle ofincidence is about 15 degrees.

14. A high speed data processing system wherein the data processingapparatus of claim 2 is located above and one same such apparatus islocated below a film path to form a pair of data processing units whichwhen in operation exert a substantially equal and opposite pressureagainst a continuous moving film passing between said units.

15. A high speed data processing system wherein the data processingapparatus of claim 6 is located above and one same such apparatus islocated below a film path to form a pair of data processing units whichwhen in operation exert a substantially equal and opposite pressureagainst a continuous moving film passing between said units.

16. A high speed data processing system as in claim 14 wherein a seriesof paired data processing units are present thereby forming a film paththrough which film can be processed.

17. A high speed data processing system as in claim 16 wherein said thinoutlet aperture is about inch in width.

18. A high speed data processing system as in claim 16 wherein saidbarrier means is comprised of a polytetrafluoroethylene smooth surfaceand wherein said thin outi let aperture is about inch in width.

19. A high speed data processing system as in claim 15 wherein said thinoutlet aperture has a width of less than about inch and wherein saidangle of incidence is from about 15 degrees to about 25 degrees.

References Cited UNITED STATES PATENTS 3,405,627 10/1-968 Day et al. 943,027,821 4/1962 Wright 9589 3,093,052 6/1963 Burner et al. 95-943,192,846 7/1965 Wright 9594 3,344,729 10/1967 Kitrosser 95--89 NORTONANSHER, Primary Examiner C. E. SMITH, Assistant Examiner US. Cl. X.R.9594

